Combined square and bevel-protractor.



PATENTED DEG. 2'7, 1904.

L, S. STARRETT.

COMBINED SQUARE AND BEVEL PROTRACTOR.

APPLICATION FILED SEPT. 25. 1908.

fzgfw WT/VESSES z/Mm UNITED STATES Patented December 27, 1904.

PATENT OEEIcE.

LAROY S. STARRETT, OF ATHOL, MASSACHUSETTS, ASSIGNOR TO L. S. STARRETT (10., OF ATHOL, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS.

COMBINED SQUARE AND BEVEL-PROTRACTOR.

SPECIFICATION forming part of Letters Patent No. 778,808, dated December 27, 1904.

Application filed September 25, 1903. Serial No. 174,635-

To aZZ whom it may concern.-

Be it known that I, LAROY S. STARRETT, of Athol, in the county of orcester, and State of Massachusetts, have invented certain new and useful Improvements in a Combined Square and Bevel-Protractor, of which the following is a specification.

This invention combines in one tool a square, bevel-protractor,inclinometer, plumb, and level without the complexities which have sometimes accompanied tools for one of such purposes only. The characteristic feature is a head-stock or body having slotted working faces perpendicular to each other and an intermediate face oblique to and connecting both with a spirit-level adjacent and parallel to each perpendicular face. a graduated ring located in a circular opening through the head-stock near its apex and equidistant from said slotted perpendicular faces, and a longitudinallymovable grooved or slitted measuring-blade held to said ring and adjustably in the slotted perpendicular faces and angle of the head-stock by partial rotation of the ring.

In the drawings, Figure 1 is a side elevation with part of the blade broken away, and Fig. 2 is a like view showing the tool inverted and the blade held obliquely to the working faces of the head. Fig. 3 is an edge view, the blade in section on line 3 3 of Fig. 1. Figs. 4 and 5 are enlarged transverse sections on the lines 4 4; and 5 5 of Fig. 1. Fig. 6 is an enlarged central section through the oscillating ring showing its blade-seat.

The body or head-stock 7 has two arms standing at right angles to each other, their finished working faces 8 preferably intersecting a short intermediate face 2 at an angle of forty-live degrees. Integral and of equal thickness with these parts is an open circular portion 9, the side walls of each being uniformly ground and finished fiat. Back of these finished faces the body 7 is cast thinner in any desirable form and carries two spiritlevels 10, set in elongated bosses of the body parallel with the working faces 8, and hence at a right angle to each other. One level is preferably set, in relation to its working face, upside down, to use underneath, the other on top of, the work.

The perpendicular working faces 8 8 have longitudinal central slots 11 of uniform width and depth to receive and form a seat for either edge of the measuring-blade 12, which may be plain or graduated, as desired. This blade has in one of its faces a continuous groove or slot 13 running lengthwise of the blade to receive the tip of the hook, which holds it adjustably in working position.

\Vithin the circular portion 9 of the bodyI mounta ring 1 1 of equal thickness marginally with said portion and having a partial rotation therein. Said ring has at one side a broader part 15 with a central boss and is perforated radially to admit a radial bolt 16, booked at its outer end to traverse the slot in the blade and threaded on its inner end to receive a milled nut 17. This broadened part of ring 1 L has an edgewise slot 24, Figs. A and 6, corresponding to the slots 11 of body 7, with a suitable blade-seat at its bottom against which the blade 12 is firmly held when the hooked tip of the bolt 16, which extends down at one side of the blade, is in slot 13 of the blade, and nut 17 on its other end is tightened against the ring or central boss. (See Fig. 4.) A coiled spring 18, compressed within and by nut 17, tends to hold the blade edgewise and frictionally against its seat in said ring, and this prevents it from dropping out when said nut is slackened to permit longitudinal adjustment of the elongated blade to project in either Way. The blade-slot13 may be a mere groove extending from end to end and the blade inserted endwise to engage the hooked tip of bolt 16 in position in ring 1 1, or it may be a slit entirely through the blade, but not extending to its ends. In the latter case I form a perforation 25 through one of the slotted working faces 8 of the body for simultaneous insertion of the hooked bolt endwise and the blade edgewise. (See Fig. 4:.) It will thus be seen that the blade is connected to the tool-body by its described hooked connection to the ring 1A, which has an oscillatory movement or partial rotation within the part 9 of the body. Such movement readily transfers the blade from its position in the slot of one arm of the body into that of the other arm or to any intermediate position, as illustrated in Fig. 2. hen firmly seated in either slot, the blade is known to be at a right angle to the other face 8. The broadened part of ringM has on one face agraduated arc of IO ninety degrees, (see Fig. 2,) one of its termini registering with the Zero-mark 19 at the mid dle of the oblique face of the body whenever the blade is seated in either of the slotted faces 8. By this means either face 8 may be 5 adjusted to any angle between zero and ninety degrees, denoted by the position of the zeromark with relation to the scale of degrees on said are, and when adjusted the ring and blade may be fixed in position for the time being 20 by a set-screw 9.0, threaded into a boss 21 and having a bearing terminally against the wall of opening 9. The opposite side of the broadened part 15 of the ring 14 is provided with a scale 22, graduated from each terminal to a 5} central point and each half having marks to denote the pitch in inches to the foot of any inclined surface and indicate it in half-inch or smaller fraction. (See Fig. 1.) Screws 23, Figs. 1 and 2, may be inserted in the wall 3 of circular opening 9, the broad heads overhanging the edge of oscillating ring 14 to keep it in place.

It will be understood that since the two fixed arms, with their working-faces, stand at ninety degrees to each other when the adjustable blade 12 is fixed at any angle desired in relation to one working face for instance, at twenty degrees--its angle to the other face will be the complement of a right angle-that 4 is, seventy degrees. Thus the instrument serves to lay out any angle or pitch for valley roofs,&c.,to make perfect fits to form ninetydegree angles without mental calculation. So whatever pitch is used to lay out work with one arm the other arm with blade is right to make up the other component part of ninety degrees, while with the two levels any pitch desired may be leveled up from either top or under side of a roof, rafter, or 5 other thing worked upon.

Having thus described my invention, I claim- 1. The described tool, comprising the headstock or body, having arms at right angles to each other, and edgewise-Working faces perpendicular to each other, each slotted from end to end to a uniform depth to form a bladeseat, in combination with a ring mounted to oscillate in the apex of said stock or body and with a straight-edge or measuring-blade held to said ring and made adjustable into such slotted faces and intermediate position as set forth.

2. The stock or body having parallel sides or lateral portions, perpendicular working 5 faces each intersecting with an intermediate oblique face and a continuous longitudinal slot through such faces, in combination with a disk or ring, mounted to oscillate in said body, a blade-scat formed in said disk or ring, 7 coincident with said slot, and an elongated measuring-blade held to said seat and adjustable in said slot to any desired angle in relation to said faces, as set forth.

3. The stock or body having slotted working faces forming blade-seats perpendicular to each other, an oscillating ring in the apex ofsaid body, slotted edgewise to form a bladeseat, and a longitudinally-grooved straightedge or blade, adjustably held to and movable in such slots and seats, in combination with a radially-arranged hook-bolt engaging terminally in the groove or slot in the blade and provided with an adjusting-nut located in said ring, as set forth. 8

4. The stock or body having slotted work ing faces perpendicular to each other, and two spirit-levels fixed in said body respectively parallel to said faces, in combination with a disk or ring mounted for oscillation in a recess in the body, between and equidistant from its converging perpendicular grooved faces, an adjustable measuring-blade secured to such disk or ring and means for fixing. said ring and blade in any desired position when adj usted, as set forth.

5. The stock or body, having slotted working faces perpendicular to each other, a short oblique face intermediate and connecting said perpendicular faces, and an adjustable meas- I00 uring blade adapted to be held in either of such slotted faces and in intermediate positions, in combination with an oscillating disk or ring carrying said blade and provided on its faces with a graduated arc and indicatre g m a s to d not the angle which t e blade bears to the working faces of the body,

as set forth.

6. The described tool, comprising the head stock or body having arms at right angles to each other, said arms having edgewise-working faces perpendicular to each other, each arm being slotted from end to end. through said faces, in combination with a ring mounted to oscillate in said stock or body, and a 5 straight-edge or measuring-blade held edgewise to said ring and adapted to traverse said slotted faces, and adjustable therein at any desired angle thereto, as set forth.

In testimony whereof I have aflixed my I20 signature in presence of two witnesses.

LAROY S. STARRETT.

\Vitnesses:

FRANK E. WING, ERNEST W. TAYLOR. 

